post-quantum cryptography and security techniques

Quantum computing poses an existential threat to public-key cryptography, necessitating timely adoption of NIST-standardized post-quantum cryptographic (PQC) algorithms—Kyber, Dilithium, FALCON, and SPHINCS+. Method: This paper systematically evaluates PQC support across nine major open-source cryptographic libraries—including OpenSSL and Bouncy Castle—through rigorous analysis of official documentation, release notes, and real-world deployment practices. Contribution/Results: We identify substantial disparities in implementation completeness, API maturity, and production readiness: only a minority offer stable, production-grade integrations, while most remain experimental or unimplemented. To address this gap, we propose the first multi-dimensional PQC support assessment framework, quantitatively pinpointing key standardization bottlenecks. Based on empirical findings, we recommend three actionable strategies: phased migration, cross-library interoperability coordination, and development of standardized PQC testing benchmarks. Our results provide evidence-based guidance for library developers, standards bodies, and system deployers navigating the transition to quantum-resilient cryptography.

Quantum computing poses a disruptive threat to widely deployed public-key cryptosystems such as RSA and ECC. Method: This paper proposes a hybrid encryption framework integrating classical cryptography with post-quantum cryptography (PQC), systematically designing and empirically evaluating the scalability and deployability of four PQC families—lattice-based, code-based, multivariate polynomial, and hash-based schemes—in distributed environments. The evaluation combines performance modeling, quantum-resistance analysis, and cross-scenario experimental validation across blockchain, cloud platforms, and secure communication systems. Contribution/Results: The framework achieves dual guarantees of forward secrecy and backward compatibility; significantly enhances robustness against quantum attacks under bounded computational overhead; and delivers a practical, migration-ready hybrid encryption paradigm for next-generation network infrastructure requiring high security and interoperability.

This study addresses the urgent challenge posed by quantum computing to classical cryptographic systems and advocates for a systematic transition to post-quantum cryptography (PQC). It comprehensively reviews the principal PQC approaches—including lattice-based, code-based, hash-based, multivariate, and isogeny-based schemes—and provides an in-depth analysis of the threats from Shor’s algorithm, the current status of NIST standardization, and practical deployment challenges. The work introduces an innovative incremental migration architecture that integrates mathematical foundations with security engineering, bridging the gap from foundational understanding to strategic migration decisions. Notably, it delivers the first authoritative technical guide tailored for the Portuguese-speaking academic community, thereby supporting the development of a secure and coherent PQC governance framework.

This study addresses the severe threat posed by quantum computing to conventional public-key cryptography, particularly undermining the security of key authentication and digital signatures in X.509-based Public Key Infrastructure (PKI). The work systematically analyzes the integration requirements of NIST-selected post-quantum cryptographic algorithms into X.509 certificates, Certificate Revocation Lists (CRLs), and the Online Certificate Status Protocol (OCSP). It presents the first comprehensive framework for structural and protocol-level adaptations necessary to support these algorithms within existing PKI components. Through rigorous compatibility and performance evaluations, the study identifies viable migration pathways and provides concrete technical guidance and standardization recommendations for transitioning to a quantum-resistant PKI.

Executing quantum circuits on untrusted quantum cloud platforms in the NISQ era poses critical security risks—particularly concerning confidentiality and integrity—due to hardware-level vulnerabilities and noise-induced deviations. Method: This paper proposes the first security property quantification framework tailored for medium-scale noisy quantum devices. It integrates quantum program static analysis, hardware-aware noise modeling, and lightweight security verification techniques, employing heuristic strategies to assess information leakage and computational tampering risks without trusting the underlying hardware. Contribution/Results: The framework delivers computationally tractable and interpretable security evaluations. Experimental validation on real NISQ devices demonstrates its effectiveness in identifying security risks for representative quantum algorithms—including VQE and QAOA—thereby significantly enhancing the practicality and systematic rigor of security assessment in quantum cloud computing scenarios.

Quantum computers pose an existential threat to current public-key cryptography, necessitating urgent development of quantum-safe technologies. This study conducts the first three-tier bibliometric and systematic review of quantum cryptography, synthesizing insights from 51 review articles indexed in Scopus. Methodologically, it integrates multi-level review synthesis, topic modeling, and challenge clustering to systematically identify QKD’s technological dominance and cross-scheme bottlenecks. Key contributions include: (1) distilling six core challenges—implementation cost, decoherence, key rate, transmission distance, quantum hacking, and quantum error correction; (2) clarifying migration pathways for post-quantum cryptography and critical milestones for quantum cryptographic deployment; and (3) proposing the first three-dimensional analytical framework encompassing technological evolution, implementation barriers, and future research directions—providing empirically grounded guidance for policy formulation and R&D investment.

Quantum computing poses a significant threat to classical cryptographic protocols based on RSA and elliptic curve cryptography, necessitating a systematic assessment of their vulnerabilities and post-quantum migration pathways. This study presents the first comprehensive comparison of structural barriers and deployment disparities across nine widely used protocols—including TLS, IPsec, and BGP—during post-quantum transitions. Drawing on both literature review and empirical analysis, it examines hybrid key exchange mechanisms, standardization progress, and real-world deployment cases. The findings reveal that key exchange generally proves more amenable to migration than authentication; TLS and Signal have already achieved large-scale hybrid deployments, whereas DNSSEC and BGP confront fundamental challenges due to signature size constraints. Crucially, message size and fragmentation limitations emerge as more critical bottlenecks than algorithmic performance.

This work addresses the challenges of migrating legacy software to post-quantum cryptography (PQC), including probabilistic behavior, side-channel vulnerabilities, and performance–security trade-offs, which existing tools struggle to manage. To this end, the paper introduces a novel paradigm—Quantum-Safe Software Engineering (QSSE)—that frames PQC migration as a systematic software engineering problem. It presents the Automated Quantum-safe Adaptation (AQuA) framework, built upon three technical pillars: PQC-aware static vulnerability detection, semantic-level program refactoring, and hybrid formal verification. Integrated with joint modeling of performance and security, AQuA offers a scalable toolchain architecture that lays the foundation for next-generation software engineering practices oriented toward quantum resilience.

This study addresses the usability challenges of post-quantum cryptography (PQC) APIs, which—due to their high complexity and developer-unfriendly documentation—often lead non-expert developers to misuse them and inadvertently introduce security vulnerabilities, thereby hindering real-world deployment. As the first systematic investigation into PQC API usability, this work empirically evaluates how developers interact with NIST-standardized PQC algorithms under minimal training, employing user studies, task observations, and cognitive analyses. The findings uncover critical issues including inconsistent terminology, a lack of canonical workflow examples, and insufficient interactive guidance. These insights provide empirical grounding and concrete design recommendations for building more usable PQC development support systems that better serve practitioners transitioning to quantum-resistant cryptography.

This study addresses the synergistic threat posed by quantum computing and artificial intelligence to current cryptographic systems: Shor’s algorithm can break public-key schemes such as RSA and ECC, while AI-driven side-channel attacks can circumvent physical countermeasures. The paper presents the first systematic evaluation of cryptographic vulnerability under combined quantum–AI attacks and proposes a defense-in-depth framework integrating post-quantum cryptography (ML-KEM/ML-DSA and SLH-DSA), implementation hardening, and cryptographic agility. Findings indicate that lattice-based and hash-based signatures resist known quantum attacks but remain susceptible to side-channel leakage at the implementation layer; symmetric encryption retains security in the quantum setting only if key lengths are doubled to compensate for halved effective strength. This work underscores that cryptographic security must be treated as a continuously evolving process and offers a practical roadmap for mitigating coordinated quantum–AI threats.

This study addresses the prevailing overemphasis on technical aspects in current research on integrating post-quantum cryptography (PQC) into software systems, which largely overlooks the critical interplay of human and organizational factors. Drawing upon a Human–Organization–Technology (HOT) triadic framework, the work employs a Systematization of Knowledge (SoK) methodology to conduct a cross-dimensional, structured analysis of existing PQC implementation literature. It introduces the first PQC-HOT integration model, elucidating the interdependencies and mutual constraints among the three dimensions and thereby transcending conventional paradigms focused solely on algorithmic performance. The proposed model not only conceptualizes PQC deployment as a socio-technical systemic transformation but also offers practitioners a systematic decision-support framework while outlining future research directions and design implications for sustainable and scalable PQC transitions.